1. Field of the Invention
The present invention relates to a copying machine for generating copies of an image on an original document, a copying-operation control device for controlling operations of a scanner and a printer for a copying operation, and a computer readable recording medium for operating a computer as such a copying-operation control device.
2. Related Art
Some types of copying machines allow a user to designate copying conditions (e.g., density and magnifying power) for the next copying work when the copying machine performs a copying operation. Those types of copying machines are disclosed in JP-A-62-166369, JP-B-2820262, JP-B-2901688 and others.
Those copying machines are of the analog type in which an image on an original document located on a document table is directly imaged on a photosensitive drum, and the formed image is developed onto a copy sheet by electrophotography technique. A recent general copying machine is made up of a reading section for generating image data representative of an image on an original document, a printing section for printing a picture representative of the image data, and a control section having copying conditions accepting function for accepting a designation of copying conditions and control function for controlling the reading section and the printing section in an integrating manner and causing the printing section to generate copies of the document image.
In this type of copying machine (referred to as a digital copying machine), the process executed by the mechanical system in the analog copying machine is allotted to the control section, and electronically executed.
Specifically, the control section of the digital copying machine executes a procedural process as shown in FIG. 18 when a copy start is instructed (when a copy start button is depressed). The procedural process illustrated in the figure is executed when the copying machine with an automatic document feeder generates one copy of a document image under control of its control section.
Namely, the control section instructs the reading section to read an image on a first original document (step S300). When the printing section can accept a predetermined amount of data (step S301; YES), the control section judges whether storage image data (to be described in detail later) is stored (retained) (step S302). If the storage image data is not stored (step S302; NO), the control section transfers a predetermined amount of image data (usually image data of several lines) from the reading section to the printing section (step SS303). Thereafter, the control section judges whether the reading process of the original document is completed (step S306), and if the reading process is not completed (step S306; NO), the control section executes the process that starts from the step S301.
The procedural steps mentioned above is progressively and repeatedly executed, and the printing section is put in a state that it cannot accept the data (step S301; NO), the control section obtains a predetermined amount of the image data from the reading section, and stores it as storage image data into an internal memory (step S305). Then, the control section judges whether the reading process of the document image is completed in the step S306.
When the control section recognizes that the storage image data is present in the internal memory (step S302; YES) and the printing section can accept the data (step S301; YES), the control section supplies a predetermined amount of the storage image data (which was earliest stored) to the printing section, and abandons the storage image data (makes free the memory area storing the storage image data having been supplied) (step S304). Then, the control section obtains the image data from the reading section and stores it (step S305), and executes (judges) a process of a step S306.
The control section progressively operates according to the procedural steps mentioned above, and when the reading process of the document image is completed (step S306; YES), the control section judges whether the storage image data is present (step S307). The control section judges whether the supplying of one sheet of the image data to the printing section is completed on the basis of the result of the judgment of whether the storage image data is present.
When the storage image data is present (step S307; YES) the control section waits till the printing section becomes ready for accepting the predetermined amount of data. When the printing section becomes ready for accepting the data (step S308; YES), the control section supplies the predetermined amount of the image data to the printing section and abandons the data (step S309), and the control section returns to the step S307.
The control section gets out of a loop consisting of steps S307 to S309 when the storage image data is used up (step S307; NO), and judges whether the next document is present (step S310). At a stage that the document reading operation ends (step S306; YES), if the storage image data is not present (step S307; NO), the control section executes the step S301 to judge whether the next document is present without executing the step S308 and the other.
If the next document is present (step S310; YES), the control section instructs the reading section to read an image on the next original document (step S311), and then executes again the process starting from the step S301. If the document to be copied runs out (step S310; YES), the control section ends the illustrated process.
As described above, the related digital copying machine repeats the execution of the process every document, as the analog copying machine does so.
Accordingly, in the related digital copying machine, even if it is of such a type that copying conditions maybe set during the execution of a copying process, when the machine is executing a copying process on a document, it is impossible to start a copying process on another document. The reason for this is that the related copying machine, in which the execution of a copying process progresses, rejects the setting of another document thereto (or does not start the reading of the document set) till the current copying process execution ends.